Machine vision vehicle alignment systems using movable cameras and targets attached to vehicle wheels are well known. The targets are viewed by the cameras such that image data obtained for a prescribed alignment process can be used to calculate vehicle alignment angles for display through a user interface, usually a computer monitor. Early system implementations included rigid beams that connected the cameras so that their position and orientation with respect to each other could be determined and be relied upon as unchanging. Later system implementations were introduced comprising the use of cameras not rigidly connected to each other, but using a separate camera/target system to continuously calibrate the position of one vehicle mounted target viewing camera to another. This type of system is described in U.S. Pat. Nos. 5,724,743; 5,535,522; 6,931,340; 6,959,253; and 6,968,282, all of which are hereby incorporated by reference herein.
Camera based wheel aligner systems are typically shipped in large boxes and installed by trained technicians. The system usually includes parts that cannot be easily and safely handled by a single technician, often requiring assistance from the customers or a second technician. For example, these alignment systems comprise a camera support mechanism to allow the cameras to be positioned and directed as required to incorporate a field of view including targets attached to vehicle wheels. The camera support mechanism usually comprises of some type of solid base or beam that is fixed to the ground so that the cameras are solidly supported. Some alignment systems use solid horizontal beams that permanently fix the distance and orientation between the cameras, while other systems use solid vertical beams and cameras that travel along the beams as necessary to maintain the targets in the camera field of view. Given the constraint of maximum vehicle dimensions, the camera supporting beams are long and heavy enough to make handling during installation difficult for a single person. A need exists for a more modular installation approach using parts that can be easily handled by one person.
In addition, each installation site poses specific challenges with regard to the physical limitations of the shop environment, including the availability of power and floor space. Space constraints and power availability locations of the specific shop create problems that cannot be solved by a large, inflexible system.
Once installation is complete, the system is typically fixed to the floor and cannot be easily relocated or adjusted by the end user. Accordingly, a need exists for an alignment system that can be moved safely and easily by an end user when a need is identified, and has the flexibility for minor adjustment without physical movement of the supporting structure.